FOR TRICHOLOGICAL PROSTHESES".

Technical field

This invention relates to an apparatus for detecting features of the head of a user. This invention also relates to a method and to a plant for making models for caps for trichological prostheses.

This invention applies in particular to making customised trichological prostheses.

Background art

In order to make trichological prostheses, making a cast is known, usually a plaster cast, directly on the head of the client so as to define the shape of his or her skull.

After having made the cast, the coordinates of all points of the surface of the cast are detected, including the line of demarcation between the area corresponding to that without hair on the head of the user and the rest. This detection is carried out by means of a tracer whose end is movable on the surface of the cast.

The data acquired are sent to a processor which transfers them to a numeric control milling machine which can operate along the three orthogonal axes.

The milling machine makes a copy of the cranial vault of the user by removing material from a block made of plastic depending on the data received.

On the copy of the cranial vault the line of demarcation between the portion corresponding to the area covered by hair and that without hair is marked. A thin layer of polyurethane resin is spread on the copy of the cranial vault to make a cap whose size corresponds to the part of the head to be covered with the prosthesis, delimited by the line of demarcation.

That method has several disadvantages. Indeed, it is always necessary to make a cast directly on the head of the client: this operation is very troublesome, takes a long time and does not always give optimum results.

Moreover, detecting the shape of the skull by means of a tracer can only be done for making “partial” prostheses, that is to say, which only partially cover the skull.

In the case of total baldness, it is necessary to make a larger prosthesis starting from a cast of a more extensive zone of the head, from the forehead to the nape of the neck. In a cast of this type, the movable tracer is not capable of performing a complete detection.

Therefore, in order to make “complete” prostheses, at present the plaster cast is filled with foam and the cap is obtained manually.

Disclosure of the invention

The aim of this invention is to allow optimum reproduction of the features of the head of a user.

A further aim is to minimise action on the user.

Yet another aim is to simplify the making of every type of prosthesis, whether partial or complete.

The invention achieves the aim by means of an apparatus having the features defined in claim 1.

The invention relates to a method having the features defined in claim 8 and a plant having the features defined in claim 17.

Brief description of the drawings

Further advantages and features of this invention will be more apparent in the detailed description which follows, with reference to the accompanying drawings, which show an example, non-limiting embodiment, in which: - Figure 1 illustrates a first preferred embodiment of a detecting apparatus according to this invention;

- Figure 2 illustrates a second preferred embodiment of a detecting apparatus according to this invention;

- Figure 3 illustrates a preferred embodiment of the working apparatus at the start of the working step;

- Figure 4 illustrates the apparatus of Figure 3 in a working step;

- Figure 5 illustrates the apparatus of Figure 3, in a step after the milling;

- Figure 6 illustrates the apparatus of Figure 3 in a step of drawing the line of demarcation.

Preferred embodiments of the invention

In Figure 1, the numeral 1 denotes an apparatus for detecting the features of the head of a user, in a first embodiment.

According to the invention, the apparatus 1 comprises a support 2 extending substantially longitudinally, at least one arm 3 connected to the support 2 and having at least one portion 31 positioned transversally to the support 2, and at least one scanning device 4 positioned at one end 32 of the arm 3.

The scanning device 4 is preferably of the optical type, comprising for example at least one video camera.

Preferably, the apparatus 1 comprises a positioning support 5 joined to the support 2. Advantageously, the support 2 is extendable. The support may for example be telescopic.

In the embodiment of Figure 1, the support 2 extends substantially vertically.

The apparatus 1 advantageously has a curved first arm 3, which extends from the upper end 21 of the support 2 and has at least one scanning device 4 at one end 32. Preferably, the apparatus 1 has at least one second arm 7 having a first end 71 connected to the first arm 3. At least one scanning device 74, in particular of the optical type, for example a video camera, is positioned at the free end 72.

In the embodiment illustrated in Figure 1, the first arm 3 has a block 6 at one end 32. The block 6 comprises at least one scanning device 4, in particular of the optical type, for example a video camera. The second arm 7 is joined to the block 6 at the first end 71.

In particular, the apparatus 1 has a plurality of arms 7, for example four, each having a first end 71 joined to the block 6 and a free second end 72. At least one scanning device 74, in particular of the optical type, for example a video camera, is positioned at the free end 72 of each arm 7. Each arm 7 is preferably curved, with the free end 72 directed towards the lower part of the apparatus 1.

The apparatus 1 illustrated in Figure 1 has five arms, of which one arm 3 is directly connected to the support 2, and five video cameras, a central video camera 4 and four lateral video cameras 74, which are arranged substantially in a circle, in such a way as to carry out the scan of a zone positioned below the central block 6.

In the embodiment illustrated, the arms 3, 7 are fixed.

In one embodiment not illustrated, the apparatus comprises at least one arm movable on a substantially circular trajectory around the zone located between the support and the second end of the arm, on which a video camera is positioned.

The lower part of the support 2 is joined to a base 8, in particular provided with castors 9.

The apparatus 1 comprises a positioning support 5 for the chin of a user, positioned on the support 2. The apparatus preferably comprises a data acquisition and processing system 10 connected to the scanning device 4. The system 10 comprises an interface 11 for manual data entry.

In use, the user positions himself or herself in the zone located between the support 2 and the arms 7, in particular below the central video camera 4, resting the chin on the positioning support 5.

Preferably a check is carried out to ensure that the user is correctly positioned relative to the scanning device or devices 4, 74.

A line of demarcation between the part without hair and the part with hair is preferably marked on the head.

The user data are entered and the scan is started.

The scan data are acquired by the system 10 which processes them in such a way as to obtain a digital three-dimensional model of the head. The model comprises the data relative to both the shape of the skull and the distribution of the hair.

If multiple scanning devices are present, the alignment of the images obtained by the various devices is performed and checked.

Advantageously the processing of the digital model comprises application of the spline algorithm or interpolation.

Indeed, before detection, a film is applied on the head of the user which increases the luminosity in circumscribed areas, making detection by the scanning devices difficult. Application of the spline algorithm solves the problem of light concentration by reconstructing the head in the zones not detected based on measurements available around them.

The apparatus 1 of Figure 1 allows detection of the features of the head directly on the user, avoiding making plaster casts. Figure 2 illustrates a second embodiment of an apparatus G. In that embodiment the support T extends substantially horizontally. In particular, the support T is extendable, for example telescopically.

The arm 3’ extends along a substantially vertical line, starting from a first end 2G of the support 2’. At least one scanning device 4’, for example a video camera, is positioned at the free end 32’ of the arm. The scanning device 4’ is preferably movable.

Positioned at a second end of the support 22’ is the positioning support 5’.

The second embodiment is suitable for performing the scan of casts, for example plaster casts, of the head of a user.

In use, after having made the cast and drawn the line of demarcation inside it, the cast is fixed on the positioning support 5’, preferably in such a way that the cavity of the cast is directed upwards.

In this way the scanning device 4’ acquires the complete image of the inside of the cast. The scanning device 4’ is capable of detecting the features of the inside of the cast whether it is a partial cast (which has a depth of approximately 5-6 cm) or it is a complete cast (which has a depth of approximately 10-14 cm).

The apparatus G preferably comprises a data acquisition and processing system 10’ connected to the scanning device.

As in the embodiment of Figure 1, the scan data are acquired by the system which processes them in such a way as to obtain a digital three-dimensional model of the head. The model comprises the data relative to both the shape of the skull and the distribution of the hair. In both of the embodiments, the digital model obtained is saved and can be transmitted to another processor. The model can be transmitted as any digital file, even by electronic mail or via internet.

The digital model is transmitted to a control system associated with a working apparatus 15 for making a copy of the cranial vault of the user (Figure 3). Advantageously, in the control system the digital model is processed in such a way as to consider only the parts of the head which are useful for making the cap, in particular the upper part of the skull in which the line of demarcation is marked.

Preferably in the control system the height of the copy of the cranial vault on which to make a cap is defined.

Indeed, the height varies depending whether the cap to be made is a cap for a complete prosthesis or for a partial prosthesis. In the former case the height is approximately 20 cm. In the latter case the height is approximately 12-15 cm.

In the embodiment illustrated in Figure 3, the apparatus 15 comprises an anthropomorphic robot 16 having at least one arm 17 provided with a milling tool 18 positioned at the free end 172 of the arm 17.

The apparatus 15 comprises a resting table 19 on which at least one solid block 20, in particular made of plastic material is positioned (Figure 4).

By means of the milling tool 18, the anthropomorphic robot 16 makes a copy 21 of the cranial vault based on the data supplied by the control system relative to the digital model (Figure 5).

Advantageously, the anthropomorphic robot 16 has a writing tool 22, for example a pen, for marking on the copy 21 made of plastic the line of demarcation based on the data supplied by the control system (Figure 6). The hair installation perimeter is therefore precisely defined. Preferably, the writing tool 22 is movable from a first position away from the end 172 of the arm 17 of the anthropomorphic robot 16 to a second position near the end 172 of the arm 17, for drawing the line. In the first position the writing tool 22 does not interfere with the milling operation.

Advantageously, the robot 16 makes a plurality of copies 21 starting from a single block 20.

Preferably, the resting table 19 is rotated around a vertical axis in such a way as to shift the block 20 and the copies 21 relative to the anthropomorphic robot 16.

In one advantageous embodiment, the inclination of the writing tool 22 is adjustable, in such a way as to always make a stroke with constant pressure avoiding cutting and making grooves in the surface of the copy 21 made of plastic.

It is therefore possible to make a customised prosthesis with extreme precision.

Indeed the acquisition apparatus allows precise detection of all features of the head of the user, both relating to the shape of the skull and the distribution of the hair. The features are then processed to create a three-dimensional digital model which is transmitted directly to the apparatus which performs the milling of the copy made of plastic.

The acquisition no longer takes place by means of a tracer movable on a plaster cast, and it is therefore possible to precisely supply the data relative to the entire shape of the skull, which are necessary for making a complete prosthesis.

According to this invention, a method for making models for the production of caps for trichological prostheses comprises the steps of: detecting features of the head of a user or of a cast of the head of a user; processing digital data corresponding to the features detected; transmitting the digital data to a working apparatus; making at least one copy of at least one portion of the head corresponding to the digital data starting from a solid block, in particular made of plastic material. The working apparatus for making the copy comprises at least one anthropomorphic robot 16 having at least one arm 17 provided with a milling tool 18 at the free end 172. Preferably, the method comprises a step of drawing on the head of the user or on the cast a line of demarcation between the zone in which hair is present and the zone without hair before carrying out the detecting operation.

Advantageously the anthropomorphic robot 16 comprises a pen 22 for drawing the line of demarcation on the copy.

The pen 22 is movable from an away position during the milling to a position near the free end 172 of the arm 17 at the end of the milling.

The inclination of the pen 22 relative to the copy is adjustable and is kept constant during the drawing to reproduce the line of demarcation on the surface of the copy without cutting it.

The method comprises a step of processing the digital data to obtain a model of the substantially upper portion of the skull comprising the line of demarcation. The copy made of plastic material is made starting from the model.

Advantageously, the method is implemented starting from the images of the head of the user acquired by means of the apparatus of Figure 1. In this way it is possible to avoid making the cast, making the process easy for the user and obtaining more precise data relative to the features of the head.

Alternatively, the method may be implemented starting from the images of the cast acquired by means of the apparatus of Figure 2 or starting from coordinates detected with other instruments. According to one aspect of this invention, a plant is supplied comprising at least one first apparatus for detecting features of the head of a user having at least one scanning device, in particular of the optical type, and a data acquisition and processing system connected to the scanning device and suitable for obtaining a digital model, in particular three-dimensional, of the head of the user; at least one second working apparatus for making at least one copy of at least one portion of the cranial vault corresponding to the digital model starting from a solid block, in particular made of plastic material; and a control system operatively interposed between the first apparatus and the second apparatus for transmitting to the second apparatus the data relating to the model for making the copy.

The first apparatus is advantageously the apparatus illustrated with reference to Figure 1

The second apparatus advantageously comprises an anthropomorphic robot described with reference to Figures 3-6.